ESP-Hosted project provides a way to use ESP32 as a communication processor for Wi-Fi and Bluetooth/BLE connectivity. On the host side, ESP-Hosted offers a standard network interface for receiving and transmitting 802.3 frames. On top of the network interface, the host can use its own TCP/IP and TLS stack. For BT connectivity, a standard HCI interface is exposed to the Bluetooth host stack.
Please note that this project doesn't provide a standard 802.11 interface to the host. For the control path between the host and ESP32, ESP-Hosted uses a custom implementation based on Protobufs.
ESP hosted solution provides following WLAN and BT/BLE features to host:
- WLAN Features:
- 802.11b/g/n
- WLAN Station
- WLAN Soft AP
- BT/BLE Features:
- v4.2 BR/EDR and BLE
ESP-Hosted solution supports microprocessors running Linux as well as STM32 MCU (STM32F469I). It's possible to port this relatively easily on other MCUs too. We support Raspberry-Pi (3 Model B+, 4 Model B) and STM32 Discovery Board (STM32F469I-DISCO) out of the box.
ESP-Hosted uses SDIO and SPI as the transport interface for data and control path. The host acts as SDIO or SPI master whereas ESP32 acts as a corresponding slave. Currently Raspberry Pi supports both SDIO and SPI transport and STM32 supports SPI transport.
For detailed explanation, please go through -
Below table explains which feature is supported on which transport interface for Linux based host.
| Transport Interface | WLAN support | Virtual serial interface | BT/BLE support |
|---|---|---|---|
| SDIO | Yes | Yes | Yes |
| SPI | Yes | Yes | Yes |
| UART | No | No | Yes |
Below table explains which feature is supported on which transport interface for MCU based host.
| Transport Interface | WLAN support | Virtual serial interface | BT/BLE support |
|---|---|---|---|
| SDIO | No | No | No |
| SPI | Yes | Yes | HCI interface can be implemented over virtual serial interface |
| UART | No | No | No |